contains fusel oils which, with alcohol, are responsible for hangovers. Without lobster butter and brandy, the Newburg sauce is pretty unattractive, so let's forget that.

Ah well, you'll say, "I'll just make a meal of potatoes." Let's see whether you'll be safe. One thing is sure: if you don't want to eat foods that contain additives, then you shouldn't want to eat foods containing similar chemicals added by nature.

Potatoes, like all members of the nightshade family, contain glycoalkaloids. The alkaloid in potatoes is solanine. It is a cholinesterase inhibitor; that is, it interferes with the transmission of nerve impulses in much the same way as nerve gases. The solanine is near the skin, along with the vitamin C. Therefore, the solanine content is particularly high in potatoes that have a high skin to volume ratio; that is, in new potatoes. The safety factor may only be ten or less. If you find yourself feeling drowsy or paralyzed or having difficulty breathing after your next bite of potatoes, it might have been the solanine at work. Potato poisoning is no joke. It was common years ago when potatoes were a major item of the diet and in times of food shortages.

What about the parsley and butter? Sorry, relief is not yet in sight. Butter we have discussed. Parsley contains psoralen, a photosensitizer. Rubbed on the skin or consumed by mouth in sufficient quantity, it produces an unusual sensitivity to sunlight, resulting in severe sunburn or tanning. Furthermore, parsley contains the hallucinogen, myristicin, same as carrots. No parsley for you.

Broccoli contains not one, but five goitrogens, two of them in large quantity. These different promoters

of goiter, and the chemicals our bodies produce from them after we eat the broccoli, act at five different points in our metabolism - our use of iodine. It is somewhat like kinking your garden hose in five different places. Skip the broccoli.

Hollandaise sauce without anything to eat it on is not very attrac tive, but our food is getting scarce, and we will not discard it on that account. Let's see now. Our hollandaise sauce was made with egg yolk, butter, and lemon juice. We'll skip the cholesterol in egg yolk, and in this toxicology exercise consider only its vitamin A and vitamin D content. We know about vitamin A. Vitamin D, another of the fat-soluble vitamins, is tolerable only with an even narrower margin of safety. For adults, the safety margin with vitamin D is about 10-fold; for infants, it is probably less than five. Lemon juice contains a host of very questionable substances. Citral, for example. Given orally to animals, citral damages the lining of the circulatory system, and the optic nerve, and is a vitamin A antagonist; that is, it counteracts the good effects of vitamin A. Synephrine is a pressor amine, which we shall discuss shortly, and isopimpinellin is a photosensitizer, similar to the psoralen in parsley. Nix the hollandaise.

A nice white wine is just the thing for such a tasty meal. Well, it might have been but you don't have to be a teetotaler to ask the waiter to take it away. The principal ingredient of toxicological interest in wine is, of course, the alcohol. It may also contain pressor amines, and a number of other substances not acceptable under these criteria. Carry Nation would feel vindicated.

Parsley

• Psoralen (a furocoumarin) • Myristicin

Broccoli

• (R)-2-Hydroxy-3-butenylglucosinolate

(Progoitrin)

3-(N-Methoxyindolylmethyl

glucosinolate (neoclucobrassicin) Allyl glucosinolate (sinigrin) 3-Indolylmethylglucosinolate 3-Butenyl glucosinolate (gluconoapin) Hollandaise Sauce

Egg Yolk

Cholesterol • Vitamin A • Vitamin D Butter

Wine

Vitamin A

• Alcohol

• Tyramine • Fusel Oils • (Tanins)

Lemon Julce

• Citral

• Synephrine Isopimpinellin

Wine

• Alcohol

• Tyramine

../

Safe at the Plate (Cont. from page 9)

SALAD

In our salad, watercress, like the radishes and broccoli already discussed, contains a goitrogen. That would be enough to eliminate watercress. But in addition to that, weight for weight, watercress contains twice as much dangerous vitamin A as butter, and also an unknown something, an 'anti-vitamin,' that ties up and renders vitamin B, ineffective.

A moment ago when discussing lemons we mentioned synephrine, a pressor amine. Such chemicals tend to raise the blood pressure. Avocados contain a number of pressor amines. For most of us, the consumption of a normal diet containing pressor amines has little effect because our bodies contain an enzyme system, monoamine oxidase, which rapidly and effectively chews these amines up into fragments we can utilize or excrete. But some people have reduced monoamine oxidase capacity, particularly if they have been taking antidepressant drugs, such as Parnate. Moreover, the potential adverse effects of the pressor amines are not restricted to those on antidepressants. We will take this point up later on. However, we have good reason to pass up the avocado.

Lemon-herb dressing is a "no-no" by our far-fetched application of the federal standards for added toxicants to those naturally occurring in our food. We have already discussed the hazards of lemon juice. Among the herbs, the pepper contains myristicin, the parsley has myristicin and psoralen, and the onions have the disulfide goitrogens. Egg white contains avidin, a biotin antagonist which ties up that vitamin in an unusable form. The red pimento contains vitamin A. The dill contains more myristicin; the vinegar, acetic acid; and the vegetable oil, like most samples of vegetable oil, contains the now familiar benzo(a)pyrene, a carcinogen, apparently as a result of biosynthesis in the plant. That leaves just the hearts of palm and we don't know what all they contain. BUTTER

We have already eliminated butter as an ingredient, so we cannot tolerate it as a separate, visible item. "Waiter, remove the butter, please.”

Watercress

2-Phenylethylglucosinolate (gluconasturtiin)

• Thiamine antagonist • Vitamin A

Avocado

• Serotin

• Dopamine • Tyramine

Lemon-herb Dressing

• Lemon Juice - Citral,
Synephrine, Isopimpinellin
(a furocoumarin)

• Pepper - Myristicin

• Parsley - Myristicin
and Psoralen

• Onion - Di- and Trisulfides
• Egg White - Avidin

• Red Pimiento - Vitamin A
•DI!! Myristicin

• Vinegar - Acetic acid

• Vegetable Oil - Benzo(a)pyrene

Butter

• Vitamin A

CHEESE

Cheese would be nice to have after our meal - if we'd had a meal to have something after. But cheese, like avocados, is a rich source of pressor amines, particularly tyramine. So, goodbye cheese.

FRUN

But we are not done with the pressor amines. Bananas are a major source of pressor amines, particularly serotonin. We've seen that hazards from pressor amines are not restricted to those persons taking antidepressants. Here we can draw again from human experience. Those African tribes that eat a large amount of bananas and plantains show an unusual incidence of a peculiar type of heart disease, right-sided valvular lesions. Furthermore, individuals in our own population who suffer from a tumor called "carcinoid syndrome," which causes them to produce a large amount of serotonin, suffer from the same heart lesions. This is fairly persuasive evidence that our margin of safety with bananas is not all that great. These hazards are from the dietary consumption of bananas. The pressor amines are most effective when injected. In fact, one gram, 1⁄2 of an ounce, % of a teaspoonful, of• banana pulp is equivalent to about 50,000 bee stings, which certainly makes one grateful that bananas do not have sharp points.

An apple a day keeps the doctor away? Well, let's apply our regulatory yardstick of toxic chemicals to its content. Apples' most interesting component is phlorizin, which interferes in a number of enzyme systems in our cells and produces glucosuria; that is, glucose in the urine. Several dozen apples a day will not keep the doctor away, but they would scare off your life insurance agent.

A day without oranges is like a day without sunshine? But oranges contain the flavone, tangeretin, which is embryotoxic. It is found not in the pulp juice, but in the peel juice, some of which gets into ordinary orange juice. Here the safety factor is fairly wide, probably more than 100, although one ordinarily regards embryotoxic effects as more serious than some other categories of toxicity. Oranges also contain tyramine, synephrine, and citral. So our tray of fruit is bare.

Toxicologists derive the information by which they judge the safety of the chemicals in our environment using two principal sources of information. By testing the effect of a substance fed to animals, we may reach some tentative conclusions on how the same substance may affect man. These results are always tentative. Rats, mice, or even monkeys are not simply small humans. Each species may react differently, and these differences must be studied. Within each species, individuals may differ. It is customary to allow for these differences by ap plying a safety factor of 100-fold, more or less, as we derive safe levels for human use from such animal experiments. Stated more precisely, the highest level fed to animals which causes no apparent adverse effect is normally divided by 100 in order to determine the total amount to which a human may be exposed. If the test data are not extensive, or the effects are serious, then a larger safety factor may be required. If the background of information is very broad and the adverse effects are not serious, then a somewhat smaller safety factor may be

ゆく

Food Testing

tolerated. Our Food and Drug Act, however, stipulates one major exception to this scheme. It provides that a substance that is found to cause cancer when ingested by man or animal shall not be permitted as a food additive in any amount. This is the so-called "Delaney Clause."

The second source of information about food safety is human experience. This may be experience with the substance in nature, from accidental or industrial exposures, or as a result of drug or other use. Human experince has the great advantage that it involves the species with which we are most concerned man himself. But it has a correspondingly great disadvantage. It is experience, not an experiment. It is almost never controlled. Other things are happening, other influences are at work, which may alter or cloud the results. Thus, it is seldom that we are able to associate a particular cause with a particular effect. We can speak of correlations, but not of a clear connection unless it is supported by other kinds of information.

In summary, animal tests are difficult, subject to a variety of

major uncertainties, and often hard to reproduce. With all their weaknesses and with the need for wide safety factors, they still remain a valuable source of insight into the extent of risk or safety associated with a particular substance. Yet human experience remains the final determinant. No matter how many animal tests tend to indicate safety, if a substance harms humans, we will be reluctant to use it. Conversely, we continue to eat, drink, and do many things which are hazardous, because we attach other values to them, or because the hazards appear to be small.

Other types of tests may supplement or replace these two kinds of information. A critical third factor is informed scientific judgment. This is usually based on knowledge of the chemical structure and the physiological effects of substances that are chemically

or

pharmacologically related. Such judgment tells the toxicologists what adverse effects to look for, what kinds of tests to run, what special conditions to apply. how much to trust the results, and when further testing is likely to be profitless. R.L.H.

same refining of wheat and other grains, we have also lost phytic acid. Phytic acid has a strong affinity for iron, zinc, and other minerals in the diet. In many areas of the world, such as Iran, where unleavened whole grain bread is a major item of the diet, one finds iron and zinc deficiencies with their attendant symptoms such as anemia and hypogonadism, failure to develop sexually.

We are obviously at the end of our meal, our time, and our rope.

If you wonder "What is really safe?" or "Why is he bad-mouthing all food?" then we will have failed grievously in trying to convey an essential message about the safety of our food supply.

MISPLACED CONCERN

We must not neglect any aspect of food safety. But we should pay the most attention to the greatest risks.

Through popular, misplaced, and overzealous concern we have devoted disproportionate effort and placed stringent requirements on certain minor food ingredients and exaggerated their risks. To them we apply safety standards we dare not apply to major or natural ingredients, or we would have virtually nothing to eat, as you can see from what's been said.

Behind the irony of these absurd but true examples there's a serious point. Let us have no misunderstanding. The foods in our menu are not dangerous when consumed as a normal part of a balanced and varied diet. They are nutritious and they are safe. Nothing else is implied. Nor does this suggest that we should go to the other extreme and say that because too much of anything will hurt you, we should throw caution to the winds and abandon completely any effort to weigh risks and to choose wisely. The whole point of this exercise is that there is a middle course and it is the only sensible course. Safety lies not in avoiding all risk, because we never avoid all risk. We simply choose among risks. Safety is, in fact, a path between risks, sometimes broad, sometimes narrow, sometimes clearly marked, sometimes indistinct. We cannot follow that path if we look at only part of it, if we preoccupy ourselves with only one type of risk, or the most remote risks. In total reality, pesticide residues and additives are far "safer" used with wider safety factors and more careful appraisal than many natural components. Their risks are tiny compared with the risks we run every day, through carelessness and ignorance, from food insanitation and poor nutrition. We can only make progress safely if we see the whole scene and deal with risks in the priority of their importance. We owe it to ourselves to concentrate most of our efforts on the greatest risks in our food supply and on those which can most easily be reduced. The key to food safety is three simple words: sanitation, variety, and moderation. All of us connected with the food industry, as I am, have a substantial responsibility to help people achieve understanding of this perspective in seeing the whole picture.